I had a similar problem, from what i remember it's an issue related to the signal band you're using. Probably like you said it's trying to connect in 5ghz mode to your router but it doesn't support it, so you should change the mode of connection to 5ghz to 2.4ghz. You can do it via terminal with this commands:
sudo nmcli connection modify "<SSID>" 802-11-wireless.band bg
sudo nmcli connection modify "<SSID>" 802-11-wireless.bssid "<BSSID>"
sudo nmcli connection up "<SSID>"
... A truly wise man never argues with a Unicorn
--- Mystic BBS v1.12 A49 2023/01/28 (Windows/32)
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